Concepts and variables
Variables continued
STATA commands
Explanations, hypotheses, and comparisons
The logic of control
100
This term refers to the extent to which an indicator tells us what we want to know about a concept.
What is validity?
100
This measure of central tendency is indicated by a variable's most frequent value.
What is the variable's mode?
100
This STATA command allows us to view the frequencies of different values or categories of a variable.
What is tabulate?
100
In contrast to normative theory which focuses on 'what should be', this type of theory focuses on 'what is'.
What is empirical theory?
100
Before we can make valid inference, we must control for this.
What is a rival explanation?
200
This term indicates that a measure consistently produces the same answer.
What is reliability?
200
This measure of central tendency is a variable's 'middle' value, below which half of the variable's observations are located.
What is the variable's median?
200
This command and option allows us to view the percentiles, median and mean average of a variable.
What is summarize, detail?
200
We would use this tool to test hypotheses with two categorical variables.
What is cross-tabulation?
200
Experimental methods use this technique to assign subjects to 'treatment' and 'control' groups.
What is random selection?
300
To do this is to make a variable empirically measurable.
What is operationalize?
300
A variable's dispersion can be described this way, when all observations have the same value.
What is zero dispersion?
300
This STATA command puts a variable in descending order.
What is sort?
300
In this type of relationship between X and Y, Y goes down as X goes up.
What is a negative relationship?
300
This is found where the composition of the treatment and control groups differ in ways that affect the dependent variable.
What is selection bias?
400
A variable is said to have this type of dispersion when all values of the variable are equally frequent.
What is maximum dispersion?
400
With this type of variable we can communicate exact differences between values of the variable.
What is an interval-level variable?
400
This STATA command allows us to create a graph with which we can view the frequency of the categories.
What is histogram? What is a bar chart?
400
In this type of relationship between X and Y, Y increases by the same rate across all values of X.
What is a linear relationship?
400
This type of validity indicates that we can 'generalize' our results beyond our particular study to the real world.
What is external validity?
500
When the mean average of a variable is lower than its median value, this variable distribution is said to have this.
What is negative skew?
500
Unlike the median, this measure of central tendency is said to be 'sensitive' to a variable's skew.
What is the mean average?
500
This STATA command allows us to recode a categorical variable.
What is recode?
500
We would use this tool to test a hypothesis with a categorical independent variable and an interval-level dependent variable.
What is a mean average comparison?
500
Given the high level of creative control used in the research design, these types of experiments are thought to have high 'internal validity.'
What are laboratory experiments?
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